22 Open-source and Free Network Monitoring Apps for Linux, macOS, Windows and Servers

22 Open-source and Free Network Monitoring Apps for Linux, macOS, Windows and Servers

What is a network monitor app?

A network monitor app oversees and controls a computer network's operations, providing continuous reports on traffic, bandwidth utilization, and network uptime. It can also detect and report device or connection failures.

The benefits of using a network traffic monitor include:

  • Enhanced security: It helps identify suspicious activity that could indicate a security breach.
  • Optimal performance: By monitoring network usage, it's possible to identify bandwidth hogs or bottlenecks that can slow down the network.
  • Reduced downtime: Quick identification and resolution of network issues can minimize downtime and its associated costs.
  • Planning capacity: It provides valuable data that can aid in planning for network capacity needs.

Use-cases

Network traffic monitors are indispensable tools for organizations across the spectrum, from small businesses to large enterprises. They're the go-to solution for IT departments, network administrators, and security teams. Moreover, they're invaluable assets for managed service providers (MSPs) and other IT service providers.


This list include the best open-source free network monitoring tools, for Linux, Windows, macOS and servers.

1- TrafficMonitor

TrafficMonitor is a network monitoring software with floating window feature for Windows. It displays the current internet speed and CPU and RAM usage. There are also other capabilities like an embedded display in the taskbar, changeable display skins, and historical traffic statistics.

Features of the standard free version:

  • Internet speed monitoring
  • CPU and RAM usage monitoring
  • CPU, GPU, hard disk, mother board temperature
  • Network connection details
  • If multiple network adapters are available, users can automatically or manually select networks to connect
  • Display network connection details
  • Support embedded display in taskbar
  • Support skin change and customizable skins
  • Historical traffic statistics
GitHub - zhongyang219/TrafficMonitor: 这是一个用于显示当前网速、CPU及内存利用率的桌面悬浮窗软件,并支持任务栏显示,支持更换皮肤。
这是一个用于显示当前网速、CPU及内存利用率的桌面悬浮窗软件,并支持任务栏显示,支持更换皮肤。. Contribute to zhongyang219/TrafficMonitor development by creating an account on GitHub.

2- OpenWISP

OpenWISP Monitoring is an open-source network monitoring module offering device status and network performance monitoring, as well as alert settings for network issues. It is part of the OpenWISP project and is written in Python and Django, designed to be extensible, programmable, scalable, and user-friendly.

Key Features

  • Open-source network monitoring module
  • Offers device status and network performance monitoring
  • Alert settings for network issues
  • Part of the OpenWISP project
  • Written in Python and Django
  • Extensible, programmable, scalable, and user-friendly
  • Allows any type of configuration supported by OpenWRT
  • Uses NetJSON configuration templates
  • Automatic registration to automate the deployment of new nodes
  • Modular and extensible
GitHub - openwisp/openwisp-monitoring: Network monitoring system written in Python and Django, designed to be extensible, programmable, scalable and easy to use by end users: once the system is configured, monitoring checks, alerts and metric collection happens automatically.
Network monitoring system written in Python and Django, designed to be extensible, programmable, scalable and easy to use by end users: once the system is configured, monitoring checks, alerts and…

3- Johann

Johann is a web-based tool for monitoring Cisco IOS XE devices, allowing for the collection of configuration and operational data in a structured database. It supports adding multiple devices at once and provides a structured web-dashboard for displaying device information.

Features

  • Add single or multiple devices (.csv file) at once to the johann SQLite database
  • Show device information on a structured web-dashboard
  • Update all device information
  • Show simple report graphs
  • Export database as .xlsx
  • Toolset:
    • Enable RESTCONF on a single IOS XE device
    • Test RESTCONF: Get current configuration in JSON format
    • Show logs

Supported Devices

  • ASR 1000
  • ASR 900 RSP2/RSP3, ASR 920, NCS 520 and NCS 4200
  • Catalyst 9200,9300,9400,9500,9600,9800
  • Catalyst 8000V
  • CSR 1000v
  • ESS 3x00
  • IR 1101
  • IE 3x00
  • ISR 1000
  • ISR 4000
GitHub - flopach/johann-network-device-monitoring: johann is a web-based network device monitoring tool for Cisco IOS XE devices. Collect configuration and operational data of your networking devices in a structured way in one single database!
johann is a web-based network device monitoring tool for Cisco IOS XE devices. Collect configuration and operational data of your networking devices in a structured way in one single database! - fl…

4- Picosnitch

Picosnitch is a free, open-source tool that monitors network traffic per executable, providing visualizations and notifications for new or modified network connections.

It breaks down traffic by various parameters, offers web and terminal interfaces with GeoIP lookups, checks hashes or executables using VirusTotal, caches executable hashes for performance, and detects applications running inside containers.

Features

  • Monitors network traffic per executable
  • Provides visualizations and notifications for new or modified network connections
  • Breaks down traffic by various parameters
  • Offers web and terminal interfaces with GeoIP lookups
  • Checks hashes or executables using VirusTotal
  • Caches executable hashes for performance
  • Detects applications running inside containers
  • Sends notifications for new network connections or modifications
  • Monitors bandwidth, providing breakdowns by executable, hash, parent, domain, port, or user over time
  • Differentiates multiple versions of the same app based on their hash
  • Uses BPF for accurate, low overhead bandwidth monitoring and fanotify to watch executables for modification
  • Logs parent executable and hash for each connection
  • Focuses on accurate detection with clear and reliable error reporting

Supported Systems

  • Arch Linux
  • Ubuntu
  • Debian
  • Nix
  • Python
  • Fedora, Mageie and Mandriva
GitHub - elesiuta/picosnitch: Monitor Network Traffic Per Executable, Beautifully Visualized
Monitor Network Traffic Per Executable, Beautifully Visualized - elesiuta/picosnitch

5- ntopng

ntopng is a GPLv3-licensed, web-based network traffic monitoring application. It is an updated version of the original ntop from 1998, improved in performance, usability, and features.

Install and Download

Instructions for compiling and using ntopng can be found in the doc/README.md file. Pre-built packages are available for platforms including Debian/Ubuntu LTS x64, CentOS/RedHat/RockyLinux/AlmaLinux Linux x64, Windows x64, RaspberryPI/Debian ARM, and FreeBSD/OPNsense/pfSense.

GitHub - ntop/ntopng: Web-based Traffic and Security Network Traffic Monitoring
Web-based Traffic and Security Network Traffic Monitoring - ntop/ntopng

6- Netdata

Netdata is a high-performance monitoring tool that collects real-time metrics from over 800 integrations, presenting them in low-latency dashboards.

It operates on physical and virtual servers, cloud deployments, Kubernetes clusters, and edge/IoT devices. Key features include real-time, low-latency, high-resolution data collection, and unsupervised anomaly detection using machine learning models.

Features

  • Collects metrics from 800+ integrations
  • Real-Time, Low-Latency, High-Resolution data collection
  • Unsupervised Anomaly Detection using Machine-Learning (ML) models
  • Powerful Visualization for data analysis
  • Out of box Alerts for common issues and pitfalls
  • systemd Journal Logs Explorer for log analysis
  • Low Maintenance with automated features
  • Open and Extensible, can be extended and integrates with other monitoring solutions
GitHub - netdata/netdata: The open-source observability platform everyone needs!
The open-source observability platform everyone needs! - netdata/netdata

7- Netiquette

Netiquette is a free lightweight, open-source network monitor for macOS, allowing users to view all network connections, uncover listening sockets, and filter and export network information through its simple and intuitive UI.

GitHub - objective-see/Netiquette: Network Monitor
Network Monitor. Contribute to objective-see/Netiquette development by creating an account on GitHub.

8- Skydive

Skydive is an open-source, real-time network topology and protocols analyzer. It collects topology information and flows via agents and forwards them to a central agent for analysis. All data is stored in an Elasticsearch database, and while Skydive is SDN-agnostic, it provides SDN drivers for enhanced topology and flow information.

Features

  • Captures network topology and flows
  • Full history of network topology and flows
  • Distributed
  • Ability to follow a flow along a path in the topology
  • Supports VMs and Containers infrastructure
  • Unified query language for topology and flows (Gremlin)
  • Web and command line interfaces
  • REST API
  • Easy to deploy (standalone executable)
  • Connectors to OpenStack, Docker, OpenContrail, Kubernetes
GitHub - skydive-project/skydive: An open source real-time network topology and protocols analyzer
An open source real-time network topology and protocols analyzer - skydive-project/skydive

9- Netproc

Netproc is a free and open-source tool to monitor network traffic based on processes.

GitHub - berghetti/netproc: tool to monitor network traffic based on processes
tool to monitor network traffic based on processes - berghetti/netproc

10- Fluere

Fluere stands as an unmatched network monitoring and analysis tool, expertly capturing network packets in pcap format and transforming them into the highly useful NetFlow data. Offering seamless support for both live and offline data capture, it delivers an unparalleled, detailed view of network traffic.

Featuring cross-platform support, a robust Terminal User Interface, and instant feedback during live capture, Fluere is the definitive solution for your network analysis needs.

GitHub - SkuldNorniern/fluere: Fluere is a powerful and versatile tool designed for network monitoring and analysis. It is capable of capturing network packets in pcap format and converting them into NetFlow data, providing a comprehensive view of network traffic. It also Provides Terminal User Interface.
Fluere is a powerful and versatile tool designed for network monitoring and analysis. It is capable of capturing network packets in pcap format and converting them into NetFlow data, providing a co…

11- nload

nload is a free and open-source robust console application expertly designed to monitor network traffic and bandwidth usage in real time. It masterfully visualizes incoming and outgoing traffic with two dynamic graphs, while providing valuable additional information such as the total amount of transferred data and the network usage at its peak and lowest points.

GitHub - rolandriegel/nload: Real-time network traffic monitor
Real-time network traffic monitor. Contribute to rolandriegel/nload development by creating an account on GitHub.

12- Realtime Traffic

Realtime Traffic is a powerful and reliable Linux tool designed for monitoring network traffic in real time.

It can graph rx and tx of a Linux network interface, delivering the information instantly to any modern web browser that supports WebSockets and SVG. Proudly developed at struktur AG, it stands as a testament to our technical expertise and commitment to quality.

GitHub - longsleep/realtimetraffic: Realtime Traffic is a dependency free Linux realtime traffic monitoring tool, graphing rx and tx of a Linux network interface in realtime to any modern web browser
Realtime Traffic is a dependency free Linux realtime traffic monitoring tool, graphing rx and tx of a Linux network interface in realtime to any modern web browser - longsleep/realtimetraffic

13- PHPNetMap

PHPNetMap is a free self-hosted web application for network device monitoring using SNMP v(1/2c/3) protocol, compatible with various models including 3Com/HP, ProCurve, Dell, and Extreme devices.

It displays connected hosts based on FIB or CAM switch tables and ARP table devices. Features include search within these tables, map view of connections, port status display, and the ability to change the ifAdminStatus or set ifAlias with an SNMP community with read/write permission.

GitHub - marcelofmatos/phpnetmap: Web application for ethernet mapping. PHP Software for network device monitoring with SNMP v(1/2c/3) protocol.
Web application for ethernet mapping. PHP Software for network device monitoring with SNMP v(1/2c/3) protocol. - marcelofmatos/phpnetmap

14- Nagios Core

Nagios is a powerful open-source, enterprise-class host, server, application, and network monitoring system. It is designed to help system administrators monitor and troubleshoot infrastructures, ensuring systems, applications, services, and business processes are functioning properly.

Nagios Open Source | Nagios Open Source
Nagios Core is our original open-source monitoring solution, developed for and supported by hundreds of community members. Create your ideal monitoring and

15- PHPNetMap

PHPNetMap is a web application for network device monitoring using SNMP v(1/2c/3) protocol, compatible with various models including 3Com/HP, ProCurve, Dell, and Extreme devices.

It displays connected hosts based on FIB or CAM switch tables and ARP table devices. Features include search within these tables, map view of connections, port status display, and the ability to change the ifAdminStatus or set ifAlias with an SNMP community with read/write permission.

GitHub - marcelofmatos/phpnetmap: Web application for ethernet mapping. PHP Software for network device monitoring with SNMP v(1/2c/3) protocol.
Web application for ethernet mapping. PHP Software for network device monitoring with SNMP v(1/2c/3) protocol. - marcelofmatos/phpnetmap

16- Observium

Observium is an SNMP-based network monitoring platform that supports a wide range of network hardware and operating systems. It includes all standard features in TurnKey Core, additional configurations, and recommended packages for virtual machine monitoring.

It also includes a cronjob for discovery and polling, SSL support, Adminer administration frontend for MySQL, Postfix MTA for email sending, and Webmin modules for configuring Apache2, PHP, MySQL, and Postfix. Updates may require supervision and are not configured to install automatically.

GitHub - observium/turnkey: Observium - Network Management and Monitoring
Observium - Network Management and Monitoring. Contribute to observium/turnkey development by creating an account on GitHub.

17- LibreNMS

LibreNMS is an open-source network monitoring system that supports a wide range of hardware and operating systems. It aims to be a viable project and community that encourages contribution, focuses on user needs, and offers a welcoming environment.

Its priorities are based on the Debian Social Contract, and mutual respect guides its interactions.

GitHub - librenms/librenms: Community-based GPL-licensed network monitoring system
Community-based GPL-licensed network monitoring system - librenms/librenms

18- Cacti

Cacti stands as a superior, open-source, web-based network monitoring and graphing tool. It has been expertly designed to function as a front-end application for the unbeatable data logging tool RRDtool.

With Cacti, users gain the power to poll services at intervals of their choosing, allowing for precise graphing of the resulting data. This tool is an indispensable asset for network administrators, providing a comprehensive solution to monitor and manage network traffic and server performance.

Cacti® - The Complete RRDTool-based Graphing Solution

19- Netmon

Netmon is a simple bandwidth and latency monitor for cheap home routers written in Node.js. Netmon uses SNMP to collect the bandwidth data and optionally the system ping command to collect latency data and presents them via a simple web or cli UI.

GitHub - itsgoingd/netmon: A simple network monitor.
A simple network monitor. Contribute to itsgoingd/netmon development by creating an account on GitHub.

20- OpenNetMeter (Windows)

OpenNetMeter is a free tool designed specifically for daily Windows users, offering seamless network and data usage monitoring.

Its features include precise network speed tracking, real-time session data usage, comprehensive daily data usage, an extensive data usage history spanning up to the past 60 days, and a compact yet detailed widget for displaying network speed.

GitHub - Ashfaaq18/OpenNetMeter: A simple program to monitor your network/data usage. Made for the average windows user.
A simple program to monitor your network/data usage. Made for the average windows user. - Ashfaaq18/OpenNetMeter

21- SimpleMonitor

SimpleMonitor is a Python script designed for effective host and network connectivity monitoring. It is easy to set up and provides a streamlined solution for small businesses or home networks. It also allows remote monitor instances to send results back to a central location.

GitHub - jamesoff/simplemonitor: A Python-based network and host monitor
A Python-based network and host monitor. Contribute to jamesoff/simplemonitor development by creating an account on GitHub.

22- Bandwidth monitor

Bandwidth Monitor is a cool straightforward Python script that confidently manages your upload and download tracking, along with data consumption, at no cost.

GitHub - lilgallon/BandwidthMonitor: 📈 A simple python bandwidth monitor to track your upload, your download, and the data consumed.
📈 A simple python bandwidth monitor to track your upload, your download, and the data consumed. - lilgallon/BandwidthMonitor